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Brooks B135 failure

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Brooks B135 failure

Old 01-27-15, 06:15 PM
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Brooks B135 failure

The saddle repeatedly failed to stay in place while riding. Most often, the tilt would change, kicking the front of the saddle upward when weight was placed at the back of the frame. I tried repeatedly tightening the clamp nuts without much effect. The 13mm nuts eventually stripped the cross-bolt.

I replaced them with a ⅜" diameter bolt from the hardware store. The rails on the B135 must be spread slightly for the new bolt to clear, but it works without damage to the rails. I also had to use a taper-reamer to slightly expand the square holes through the clamp itself for the new bolt to clear. However, with the larger bolt & higher torque, the seat now stays put.

Just a FYI...
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Old 01-27-15, 06:29 PM
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That's not a saddle problem, but a seatpost affixing problem.....
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Old 01-27-15, 06:35 PM
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Originally Posted by Wanderer
That's not a saddle problem, but a seatpost affixing problem.....
That's what I was thinking too but somewhere in the back of my head I remember having a seat that wouldn't hold adjustment and having the tilt mechanism incorporated in a clamp that attached to the neck of the seat post. The seat post was unadorned, having only a taper at the end and no clamp.
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Old 01-28-15, 06:22 AM
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Originally Posted by Wanderer
That's not a saddle problem, but a seatpost affixing problem.....
I agree, but the "affixing mechanism" is an integral part of the saddle. More so on the Brooks B135 than on other saddles because the Brooks uses a "double rail" design that MUST use the Brooks clamp. You can't just put this saddle on a standard "micro-adjust" seat post (without aftermarket adapters). As @cale says, a straight seat-post is required with the taper to 1" where the saddle is mounted. Since the clamp is not only part of the saddle, but also is supplied by Brooks, I consider them a single integrated unit. Therefore a clamp failure, at least in this case, is a "saddle failure."

I further posted because having a saddle rapidly and unexpectedly change angle to a significant degree while riding can be a safety hazard. I was fortunate that in all cases, my Brooks B135 tilted but slightly and then stopped, but make no mistake - it could have been worse! The situation is exacerbated by the fact that Brooks specifically recommends the B135 for riders of over 200 pounds. These are the riders for whom the factory clamp is most likely to be inadequate.

IMHO, Brooks should redesign the clamp of the B135 with a larger through-bolt and larger nuts to avoid this type of failure. The factory 13mm clamp nuts are inadequate for the recommended riders. That said, lighter riders are unlikely to have this problem.

Last edited by FarHorizon; 01-28-15 at 06:50 AM.
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